Routing chimney through ash pit?

[allpurpose]

I am interested in heating a portion of my house with wood. I have a traditional fireplace with a clean, unlined chimney. I'm open to using an insert, but because the fireplace and the living room are both small, I wonder if a smarter plan would be to put the stove in the basement.

Here's the proposal: I have an ash pit in the basement below my fireplace that measures about 20" front to back. I have lots of room in the basement, so why not run the chimney into the ash pit, up through the "floor" of the fireplace, and on up through the existing chimney? I would use 6" SS flex liner where a rigid material didn't make sense, and insulate with either vermiculite or a pre-fab insulation kit from the liner supplier.

This way I can use whatever size or style of stove I want. I would have to build a false wall of some sort inside the fireplace firebox (perhaps brick), I know, but are there other code issues I should be aware of? I attached a sketch of my idea and the fireplace, so let me know what you think.

 

[bholler]

We have done that quite a few times. It is usually for a furnace not a wood stove but it will work fine. Just make sure your basement is insulated well and you will have to brick over the fireplace opening